1. Field of the Invention
This invention relates to a reader to read the information magnetically recorded on a card such as a boarding pass.
2. Description of the Related Art
A boarding pass having a magnetic stripe has recently come into use in airports in order to simplify the examination of tickets. As shown in FIG. 1, this magnetic stripe MS is bonded on the back of the boarding pass PS and stores the passenger flight information including a flight number, seat number, passenger name, tag number, etc. The flight information is recorded on the magnetic stripe MS through parallel-to-serial conversion and modulation. Some pieces of the information are printed o the surface of the boarding pass. Passengers receive boarding passe at the traveler's counter, advance to the boarding gate to the plane, and insert the boarding passes into the reader installed at the boarding gate. The reader reads the flight information from each boarding pass to confirm that the boarding pass is effective.
The reader has four magnetic heads and four demodulation units, which cooperate to read the flight information regardless of the orientation of the boarding pass inserted into the feeding path. The first and second magnetic heads are located under the feeding path and spaced apart in the widthwise direction of the path. The third and fourth magnetic heads are arranged above the feeding path and spaced apart in the widthwise direction of the path. The magnetic stripe of the boarding pass faces the first magnetic head when the pass is correctly inserted, the second magnetic head when it is inserted with the front side back, the third magnetic head when it is inserted inside out, and the fourth magnetic head when it is inserted the front side back and inside out. Each magnetic head detects the signal recorded on the facing magnetic stripe. Each demodulation unit demodulates the signal sensed by the corresponding magnetic head and supplies the demodulated signal to the read circuit. The read circuit includes a microprocessor, which reads the flight information by extracting a series of digital data from the demodulated signal and converts them into the parallel form.
Information can be read from the boarding pass at high speed, since the magnetic stripe MS consists of four tracks TR1 to TR4, and the flight information is divided into four groups recorded on four tracks, respectively. Therefore, each magnetic head is constructed so as to read signals from the four tracks simultaneously, and each demodulation unit includes four independent demodulation ICs for processing the signals read from the four tracks, respectively.
Hence, the reader has 16 demodulation ICs in all, making it difficult to render the reader compact or to reduce the manufacturing cost thereof. In future, the magnetic stripe will have more and more tracks because of fractionation of flight information. In this case, the above problem will be all the more serious.
Moreover, since the read circuit of the reader must respond to the signal output from any demodulation unit, it is not easy to modify the software for controlling the operation of the microprocessor incorporated in the read circuit. If the number of tracks is increased, the manufacturing cost will greatly increase because it is necessary to modify the software as well as the addition of hardware.